Outdoor paging loudspeaker



July 8, 1969 F. L. SEEBINGER OUTDOOR PAGING LOUDSPEAKER Sheet M3 Filed Sept. 3, 1965 INVENTOR. fkfflf/P/C/f Z, SEFB/NGER 4 TTOR/VEV y 8, 1969 F. L. SEEBINGER 3,454,729

OUTDOOR PAGING LOUDSPEAKER Filed Sept. 5, 1965 Sheet 2 A of 5 INVENTOR. I fiewik/cA l. Sim/-65? July 8 1969 F. SEEBINGER OUTDOOR PAGING LOUDSPEAKER 3 A of 3 Sheet Filed Sept. 3, 1965 INVENTOR. flezoae/ck Z. SE'EB/NGER ATTO/QA/E) United States Patent 3,454,729 OUTDOOR PAGING LOUDSPEAKER Frederick L. Seebinger, Smoke Rise, N.J., assignor to American Trading & Production Corporation, Baltimore, Md., a corporation of Maryland Filed Sept. 3, 1965, Ser. No. 485,013 Int. Cl. H04r 9/06, 9/10 US. Cl. 179-1155 7 Claims ABSTRACT OF THE DISCLOSURE This invention relates to loudspeakers, and more particularly, to a paging type of loudspeaker suitable for high efiiciency, public address and talk-back uses.

There have been developed a number of loudspeaker designs with the objective in mind of providing enough power amplification that the speaker may be employed for audio communication at large assemblies, either indoors or outdoors, and may, by adjustment of the input signal energy, be used to broadcast warning signals, such as fire alarms, police alarms and emergency signals. Although sufficient power has often been developed for these speakers many problems attend their use, notably, the difiiculty of protecting against water and other hazards and also, of providing a unit of sufficiently rugged design that will withstand abuse but may be easily moved about. Furthermore, it is eminently desirable that the unit be readily mounted and be very easily assembled and disassembled.

The aforesaid paging loudspeakers generally comprise three main sections: the driver assembly including an interior born, a housing or cover assembly which protects certain of the critical elements of the driver transducer, and the exterior bell or horn-shaped sound-directing member. A mounting bracket is generally provided for securing the speaker to a post or the like.

The novel speaker of the present invention provides the above-noted basic constituents, but judiciously combines them and arranges the parts thereof to achieve the optimum in performance, handling, and assembling.

Accordingly, a primary object of the present invention is to provide a paging loudspeaker particularly adapted for outdoor use.

Another object is to provide a loudspeaker which is compact and lightweight but rugged enough to withstand all kinds of weather and abuse.

Yet another object is to provide a loudspeaker which may be mounted easily in a variety of dilferent locations and which may be assembled and disassembled by a person possessing minimal skills.

A principal feature of the present invention resides in a uniquely designed diaphragm assembly having built-in connectors and having the provision of easy line-up for quick and simple replacement. Another feature consists in a uniquely designed, apertured, plastic line-up ring fitted in the driver assembly of the loudspeaker, which line-up ring allows for easy assembly of the essential components in the magnetic portion of the driver assembly. The plastic ring also acts as a dirt shield and ailords acoustic response equalization in the transmission of sound within the driver assembly.

A further feature, uniquely combined with the previous features, is one which involves complete sealing of the driver and the transformer and switch assembly. This sealing is accomplished by means of the back cover casting which completely surrounds and protects an impedance changing switch and a transformer, as well as allowing for optimum placement of the electrical terminals and the associated wiring that is brought in from a source of power to the paging loudspeaker of the present invention.

Because of the design of the cover casting and of the disposition of the mounting bracket, any water which tends to accumulate is immediately shed and is prevented from collecting near the terminals or impedance changing switch, thus minimizing any possible shorting or other electrical diificulties.

An additional feature of the present invention resides in the design for the conductor-guiding means adjacent the aforesaid electrical terminals which provides strain relief for the various types of conductors or cables that are brought in and connected to the terminals. A cover, such as of plastic, is so disposed as to bear down upon the installed conductors or cable to give the requisite strain relief. The recesses on either side of the cover-retaining screws are of different sizes so that different sizes of conductors or cables may be accommodated and fed to the terminals and secured in position by the plastic cover. Thus, any strain applied through the conductor is transferred directly from the conductor to the housing, not through the terminal.

Other features of the present invention consist in the provision of an impedance changing switch (or alternatively, the provision of a volume control) which is weather-sealed into the cover assembly. Other provisions relate to a limited adjustment on the mounting bracket previously mentioned, which keeps the sides of a speaker having a square opening parallel to the ground even though the mounting position for the speaker has been changed.

Another feature resides in a novel method of securing a reflector member to the driver assembly by means of a three point arrangement which enables ready positioning and securing of the reflector member.

Other objects and advantages of the invention will become apparent from a consideration of the following specification and claims, taken together with the accompanying drawings.

In the drawings:

FIG. 1 is a perspective view of the paging loudspeaker device according to the present invention;

FIG. 2 is an exploded view of several essential parts of the driver assembly;

FIG. 3 is a side elevation, partially in section, of the paging loudspeaker;

FIG. 4 is a side elevation of the cover assembly;

FIG. 5 is a section of the cover assembly along the line 55 in FIG. 4;

FIG. 6 is a side elevation in section of the driver assembly;

FIG. 7 is an exploded view of the several parts of the magnetic assembly.

Referring now to the drawings wherein like numbers denote the same parts, there is illustrated in FIG. 1 the complete assembled paging loudspeaker device 10 comprising a loudspeaker horn assembly generally designated 12 and a housing or cover assembly 14, which houses a switch, a transformer, and the transducer portion of the driver assembly including the driving coil for the loudspeaker.

The horn assembly 12 includes an outer horn 1'6, and a reflector or intermediate horn 18. The outer horn 16 has a generally cylindrical base portion 22 and flares out into a horn portion 24 generally square at its extremity. The reflector 18 is disposed with its mouth directed toward the base portion 22 of outer horn 16.

The housing or cover assembly 14 is in the general shape of a truncated cone except for the configuration of the outside surface which has a trapezoidal, box-like portion 26 (see FIGS. 1, 4 and integral with the cover assembly 14. Also immediately adjacent the box-like portion 26 there is provided an outwardly projecting mounting section 28, also integral and formed in one casting with the cover assembly 14. A bracket generally designated 30 (FIGS. 1 and 3) is provided for mounting the paging speaker. The bracket 30 comprises a mounting plate 32, rotatable about its axis. The plate 32 is securable to a post or wall by means of screws inserted into the holes 34. The bracket 30 also comprises a rotatable housing 36, whichis rotatable in an axis perpendicular to the axis of the plate 32. The rotatable housing 36 is free to move about toothed wheel 38, the latter being afiixed to the cover assembly 14 by means of a bolt 40 which is inserted through a boss 42 and into mounting section 28 on the cover 14. The rotatable housing 36 is adjustably positioned in order to effect different orientations for the speaker by releasing wing nut 44, which, when tightened down, prevents rotation of portion 36 or rotation of plate 32. Rotation of these parts is prevented due to the fact that the wing nut 44 is turned on a tapered bolt 45 which engages a groove in an axial extension of mounting plate 32, movement of the bolt causing the axial extension to bear against the toothed wheel 38 and against the wall of housing 36. Many different positions for the loudspeaker 10 are thus available.

Referring now to FIG. 2, there is illustrated, in an exploded view, several of the components of the driver assembly of the paging loudspeaker of the present invention. A disc 46, of cast aluminum or the like, has on one side thereof, a raised integral annular portion 48. The annular portion 48 has two oppositely positioned recesses 50a and 50b. These recesses have their respective side walls formed at angles other than exact diametrical opposition, so that they will receive a diaphragm assembly 52 in only one Way, whereby connection of only the proper polarity will be established when appropriate conductors are attached to the diaphragm assembly. Thus the projections 54a and 54b, which extend beyond the normal diameter of the diaphraghm assembly 52, must be positioned to coincide respectively with recesses 50a and 50b. To accomplish this, indexing means are provided on the diaphragm assembly 52, such that one of the projections, for example 54a, has a side which is cut to match the cut in the side wall of recess 50a.

The diaphragm assembly 52 comprises a diaphragm 56, made of molded phenolic cloth or similar material. The diaphragm 56 is bonded or otherwise attached to a ring member 57, which is composed of phenolic board or the like. Element 58, which is an integrally afiixed part of the diaphragm 56 extends through the ring member 57 and a driving coil 60, consisting of a number of turns of copper wire or the like, is Wound about portion 58. The ends of the driving coil 60 are connected to pins or posts 6111 and 61b by means of leads 62a and 62b. The diaphragm 56 also has a dome-like portion 64 extending oppositely to portion 58. The dome-like portion 64 of the diaphragm fits into a dish-like portion 46a of the disc 46 when the diaphragm assembly is placed in position by the proper orientation, as described above, of the projections 54a and 54b with respect to recesses 50a and 50b. Dishlike portion 46a extends inwardly from the inside surface 46b which is on the same plane with the outside surface 46c of the disc 46. Within the dish-like portion 46 a small curved disc 47 is disposed. Disc 47 is bonded to such as by the use of an epoxy resin or the like. Dish-like surface 46a comprises a group of spaced segments 49 with openings 51 therebetween which communicate with the horn 72.

In a manner well-known to those skilled in the art the movement of the diaphragm 56 causes vibrations to be transmitted through openings 51 of the dish-like portion 46a and in turn to the interior of horn 72.

The magnet assembly, generally designated 74 (FIGS. 2 and 7) comprises an outer ring 76 and an inner ring 78 of magnetic material and an intermediate ring 80, which is composed of plastic, and fits between outer ring 76 and inner ring 78. By this means there is afforded in the assembling of the magnetic elements of the loudspeaker of the present invention great ease in lining up the elements to define the requisite air gap in which the voice coil '60 operates, as will be apparent as the description proceeds. The plastic ring 80 has on its left hand side, as it appears in FIGS. 6 and 7, two concentric ribs 84 and 86 and it will be seen by referring to FIG. 6 that when the diaphragm assembly 52 is completely assembled in position the voice coil 60 is disposed so that it can move between the ribs 84 and 86. There is effected by means of this plastic ring 80 complete protection against dirt and complete sealing of the diaphragm assembly. The plastic ring 80 has apertures 87 positioned between ribs 84 and 86 to afford acoustic response equalization in the transmission of sound within the driver assembly.

Referring to FIGS. 6 and 7, the body 82 of the magnet assembly 74 comprises a permanent magnet in the shape of a heavy cylindrical slug 83 supported by a yoke or frame member 85. The cylindrical slug 83 has a section of reduced diameter, corresponding roughly with the inside diameter of plastic ring 80, defining a shoulder 89. Within the slug 83 a piece of felt 95 is provided for acoustic damping.

In assembling the assembly 74, the plastic ring 80 is first pressed into the outer ring 76, with the rib 84 bearing against shoulder 93 in ring 76. Then the inner ring 78 is fitted within the inside diameter of plastic ring 80 with the shoulder 91 in ring 78 bearing against rib 86. The fitted combination of rings 76, 78 and 80 is positioned against yoke 85 with ring 78 abutting the cylindrical slug 83 and the plastic ring 80 is thereby seated on the shoulder 89 of the cylindrical slug 83. Thus, by this arrangement, the separate rings 76 and 78 are perfectly aligned to provide the required air gap. Were it not for this feature, other more diflicult means such as welding together the two rings would be necessary.

The assembly of rings 76, 78 and 80 is secured to the body 82 by cementing or the like. Thereafter the entire magnet assembly 74 is magnetized.

When the magnet assembly 74 is completely assembled, as shown on the right in FIG. 2, it is secured by a strap 88 which is placed over the assembly. Screws are placed through the holes provided in the strap and are fitted into bores 90a and 90b in the annular portion 48 of disc 46. The outside ring 76 of the assembly 74 is of such a diameter as to fit within the annular portion 48 and is approximately fiush with the height of the annulus.

Referring now to FIGS. 3 and 6 the disc 46 is shown as having an integral hollow projection 92 into which is fitted the inner horn 72 which is secured therein, for example, by the use of cement. Reflector 18 is secured to the disc 46 by means of three hollow circumferentially spaced studs 94 on the disc 46, only one of which is shown in FIG. 3. These studs 94 are provided with screw threads whereby the inner born or reflector 18 can be secured. The reflector itself is so formed as to have three ear-like projections 96 which are fashioned simply by stamping them out from an initially formed flange at the base of the reflector 18. Thus, when assembling the speaker of the present invention, the reflector 18 is inserted into the horn 16 and, by virtue of the aforedescribed arrangement, the ear-like projections 96 fitting over the ends of the studs 94 enable the reflector 18 to remain stable while the requisite screws are positioned for securing the reflector.

The cover assembly 14 is provided with a flange 98 having screws holes therein, and likewise, the exterior horn 16 has a flange 100, also having screw holes, which correspond with the holes in flange 98 of cover 14. The disc 46 also has screw holes 102. Thus, when four screws 104 are run through the flanges 98 and 100 and into the holes 102 in the disc 46, the cover assembly 14, the horn 16 and the driver assembly are all secured together by this common securing means. Such an arrangement affords great ease in disassembling of the loudspeaker.

Also positioned within the cover assembly 14 and secured thereto are transformer 106 (FIGS. 3 and 5) and impedance changing switch 108 having a plurality of terminals 110 to which appropriate conductors (not shown) are normally soldered. Such conductors are connected at various points or taps on the primary side of transformer 106, in a manner well-known to those skilled in the art. From the secondary side of transformer 106 a pair of conductors 111 are connected by means of lugs 112 to the pins 61a and 61b on the diaphragm assembly 52, previously described. It will be appreciated that this built-in connector feature affords very quick and easy replacement of parts, especially the diaphragm and coil assembly, or the transformer. For example, in the case where the transformer requires replacing, there is no need to disassemble the driver assembly.

Referring now to the details of the cover assembly 14, shown in FIGS. 4 and 5, the exterior portion of the impedance changing switch 108 is shown disposed in the box-like recess 26 in cover 14. The impedance changing switch is completely protected from the weather by means of the seal 113. The seal 113 comprises nut 114, an O- ring 115 and a gasket 116. The impedance changing switch is adjusted for the various numbered positions by rotation of the shaft 117 within the seal 114. As is well understood, the rotation of the shaft 117 causes the internal connections from the impedance changing switch 108 to the transformer 106 to be changed.

Terminals 118 and 120 are shown, suitably insulated from the periphery of the cover assembly 14 and provided with screws 122 and 124, to which external conductors 126 are connected from a source of energy not shown. Also, leads 127 within the cover assembly 14 to the terminals 118 and 120 complete the essential circuitry.

It will be noted particularly by reference to FIG. 4 that there are different sized recesses 128 and 130 on each side of the bore 132 in which the cover-securing screw 134 is positioned. This feature allows for bringing in conductors of different sizes to the terminals 118 and 120, which can be placed in the proper fitting recess. Then when cover 136, such as of plastic, which is seated in the shoulder 138, is screwed down, the conductors 126 are held in one of the aforesaid recesses, so that any force applied to an external part of the conductor is transferred directly to housing 14 at the recess 128 and 130, and is not transferred at the terminals 118 and 120.

Referring now to the bottom of FIG. 4 boss 42 of mounting bracket 30 is shown. Bolt 40 has been inserted through boss 42 into mounting section 28. Boss is pointed at one end and this pointed end fits into a slot 140 formed in mounting section 28. Also, two other set positions are permitted for the mounting bracket 30 by virtue of indexing means provided. Thus, the pointed end also fits into the corners 142 and 144 formed in mounting section 28 as shown in FIG. 4. By the several set positions made available, the loudspeaker is maintainable only in desired orientations.

Although certain preferred embodiments have been herewith described, it will be understood by those skilled in the art that various modifications may be made. Thus, for example, rather than an impedance changing switch, which provides for ready adjustability of the transformer impedance to match the source impedance, a volume control device of essentially similar construction can be substituted with the same weather seal as aforedescribed.

Additionally, the plastic cover 136, although found very useful, may be replaced where found necessary by a metal plate having an opening therein to accommodate armored cable where this type of installation is found desirable.

Although the paging loudspeaker of the present invention has been described as including a particular exterior horn associated with the driver assembly, it will be appreciated that the driver assembly can be utilized alone or in conjunction with a variety of other horn assemblies.

What is claimed is:

1. A paging loudspeaker comprising:

an outer horn having a flange,

a cover assembly having a flange,

a driver assembly comprising a disc member having on one side thereof a raised annular portion, a diaphragm assembly comprising a ring-shaped member, a diaphragm affixed to said member, a voice coil wound on an element integrally afiixed to said diaphragm, said diaphragm assembly being concentrally disposed within said annular portion, a magnet assembly affixed to said disc member and partly surrounding said voice coil, said magnet assembly being partially disposed within said annular portion and means for securing together said outer horn, said cover assembly, and said driver assembly by engaging the respective flanges of said outer horn and said cover assembly, said securing means being received by said disc member.

2. A paging loudspeaker comprising:

a horn assembly including an outer horn and a reflector,

a cover assembly including a transformer and impedance changing switch secured thereto,

a driver assembly comprising a disc member having on one side thereof a raised annular portion, a diaphragm assembly concentrically disposed within said annular portion, a magnet assembly partially disposed within said annular portion and secured to said disc member, the remainder of said magnet assembly being encompassed by said cover assembly, said disc member having on the other side thereof an integral, forwardly projecting hollow portion, an inner horn secured within said hollow projecting portion and communicating with said diaphragm assembly, circumferentially spaced screw-receiving studs, integral with said disc member, for engaging said reflector.

3. A paging loudspeaker comprising:

a horn assembly including an outer horn, having a flange, and a reflector,

a cover assembly, having a flange, including a transformer and impedance changing switch secured thereto,

a driver assembly comprising a disc member having one side thereof a raised annular portion, a diaphragm assembly concentrically disposed within said annular portion, a magnet assembly partially disposed within said annular portion and secured to said disc member, the remainder of said magnet assembly being encompassed by said cover assembly, said disc member having on the other side thereof an integral, forwardly projecting hollow portion, an inner horn secured Within said hollow projecting portion and communicating with said diaphragm assembly, circumferentially spaced screw-receiving studs, integral with said disc member, for engaging said reflector,

means for securing together said outer horn, said cover assembly and said driver assembly by engaging the respective flanges of said outer horn and said cover assembly, said securing means being received by said disc member.

4. In a paging loudspeaker, a driver assembly comprising:

a disc member having on one side thereof a raised annular portion, said annular portion having a pair of opposed recesses of different configuration,

a diaphragm assembly comprising a ring-shaped member, a diaphragm affixed to said member and having a voice coil wound thereon, said ring-shaped member having opposed radial projections, said projections being differently shaped to correspond to, and fit within, said recesses.

5. The combination as defined in claim 4, further comprising a pair of pins secured to said opposed radial projections and connected to said voice coil, and electrical conductors detachably connected to said pins.

6. In a paging loudspeaker, a driver assembly comprising:

a disc member having on one side thereof a raised annular portion and on the other side thereof a hollow projection, said annular portion having a pair of opposed recesses for receiving a diaphragm assembly and an associated magnet assembly, said hollow projection being designed to receive an inner horn,

index means including biased wall portions of said recesses for insuring that said diaphragm assembly References Cited UNITED STATES PATENTS 2,590,935 4/ 1952 Charlesworth 1791l5.5 2,751,996 6/1956 Levy 18l27 2,983,791 5/ 1961 Menarik 1791 3,079,471 2/ 1963 Widener 181--3l FOREIGN PATENTS 13,145 1933 Australia.

OTHER REFERENCES Scott, David, Ground Loudspeakers In Audio Engineering, pp. 18-19, October 1949.

KATHLEEN H. CLAFFY, Primary Examiner.

A. A. MCGILL, Assistant Examiner. 

